Use Dropframe for 2:3:3:2 Recorded to MiniDV?

S

SamG

Active member
Hi.

I used the Maker software to convert a 23.976 movie to 60i (2:3:3:2) in order to archive back to minidv tape.

Should the FCP timeline be set to non-dropframe for export? I know the dvx100 records non-dropframe in progessive scan, but am not sure what to set the timeline for when going back to tape. I want to be able to capture this movie with advanced pulldown in the future.

I have viewed the output of both dropframe and non-dropframe and both exhibit a pronounced flicker.

Thanks for your help.

BTW- the Maker software did a great job of creaitng a 2:3:2:3 movie. Very nice.
 
Re: Use Dropframe for 2:3:3:2 Recorded to MiniDV?

I don't know the answer to your question, but would be interested to find out myself. I suppose you could just try both ways, then recapture to test.

Andrew
Crystal Clear Media
 
Re: Use Dropframe for 2:3:3:2 Recorded to MiniDV?

If you are just archiving and want to capture with advanced pulldown in the future, then you shuld probably stick to NDF. This does not affect the picture quality in any way - it is just timecode.

I only use DF when I "master" out to tape for broadcast. This way you are given the "real" run-time of your program. I use NDF for commercials though (because nothing changes over 30-60 seconds.)

If anyone needs an explanation of the fundamental difference between NDF and DF, just let me know.

Tim
 
Re: Use Dropframe for 2:3:3:2 Recorded to MiniDV?

Tim,

I'd appreciate an explanation of the fundamental difference between NDF and DF. I've read about it in the FCP manual, but for some reason, it didn't stick.

thanks
 
Re: Use Dropframe for 2:3:3:2 Recorded to MiniDV?

[quote author=svilay link=board=FCP;num=1087319032;start=0#3 date=06/30/04 at 12:38:57]Tim,

I'd appreciate an explanation of the fundamental difference between NDF and DF.  I've read about it in the FCP manual, but for some reason, it didn't stick.

thanks[/quote]

iamloser's link is pretty good. It explains technically what goes on.
If you are interested in my abbreviated history of the DF/NDF situation, here it is (as I remember from back in college):

Back when the scientists at RCA (or maybe it was Farnsworth?) invented interlaced TV, they needed a way to "clock" the signal. Since electricity in North America flowed at 60Hz, they chose 60 fields per second. This was perfect for them because 30 frames per second was more than enough to relay smooth motion to the viewer (24 fps was the standard for film by then.)

The mistake they made was to jump the gun on adopting the standard as NTSC, and not anticipating their needs for colour in the future. (Kind of a Y2K situation.) The big problem was that when they added colour information to the signal, there wasn't enough "room" available to send the 525 lines and the colour header at the same time at 60Hz, and still make it "backwards compatible" for B&W TVs. Their solution was to send the complete colour signal at 29.97 frames per second. (59.94 Hz)

Luckily for Europe, the engineers waited to "solidify" the PAL standard until at least a year after NTSC was made official. Using the same "clock" logic, PAL uses 50 fields per second, because their electricity runs at 50Hz. They also benefitted waiting a year by an extra 100 lines of resolution - totalling 625. The best part for PAL editors is that 25 fps is 25 fps - no drop frame situation.

Back to NTSC... since it now runs at 29.97 fps no matter what, it was inaccurate to count each frame as 1/30 of a second. You end up with and extra 3.6 seconds every "counted" hour. It doesn't seem like much, unless you are a broadcaster and those extra frames can lead you to being "out" by almost a minute at the end of the broadcast day. That could be worth a couple of million $$$ during SuperBowl!
3.6 seconds equals 108 frames, so someone figured out they could make drop frame code "skip" counting 2 frames every minute except for every 10th minute. This compensates the counter for the 108 frames, and spread them out over the hour.

NDF counts every frame, which is fine for source tapes, short projects (under a couple of minutes) and film transfers (or DVX 24P) that rely on a keycode to TC relationship, but you should use DF for your timeline if you are editing a TV show. This way when the TC reads 23:00 minutes, it really is 23 minutes.

Tim
 
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